Door closers are used to automatically close doors; hold doors open for short intervals, and control opening/closing speeds of a door in order to facilitate passage through a doorway and to help ensure that doors are not inadvertently left open. A door closer is often attached to the top or the bottom of a door. When the door is opened and released, the door closer generates a mechanical force that causes the door to automatically close without any user input.
When people are in the process of entering or exiting a door, they may swing the door, which may hit persons on the opposite side of the door. This is especially noticeable around restrooms where opaque doors are necessary. In such situations, for example, person-A exiting may be in a tight quarter, and person-B entering may be in a hurry, pushing the door into person-A, causing possible harm. The probability of this accident increases in high traffic hallways or stairwells. Another use for this door device is to prevent the door from being blown open and out of control on a windy day.
According to the American Society of Safety Engineers, in 2009 alone, there were 120 accidents that required amputations, 410 accidents that caused multiple traumatic injuries and disorders, and 870 injuries that caused pain and soreness. All of these accidents happened because people did not know if there is another person on the other side of the door. The present invention is designed to prevent such accidents.